The objective of the research is to develop an effective vaccine for the treatment of lung cancer. The commercial value derives from the novelty of the lung cancer antigen, L523S, as well as the novelty of the molecular chaperone approach using hsp110. L523S is expressed in a large number of lung carcinomas and has been shown to be immunogenic. Hsp110 is a heat shock protein with strong chaperoning properties. This molecular chaperone is then naturally complexed with L523S by heat shock. Since heat shock proteins have natural immunological functions, this hsp110-L523 S vaccine may well provide an effective therapy in the treatment of lung cancer and correspondingly have significant commercial value. Two specific aims are defined. Aim 1 will be to manufacture active, recombinant hsp110 in large quantity, establish its chaperone and immune activity, and then to verify its proper binding to the 523S lung cancer antigen. Aim 2 will determine the ability of the hsp110-L523S natural chaperone complex to elicit antigen specific immune responses in mice and will compare the magnitude of these responses to conventional approaches. Effective vaccines against lung cancer have not been previously developed and the characterization of this approach could lead to highly marketable commercial product.